libgetopt-ocaml-dev binary package in Ubuntu Xenial arm64

 This package provides the Getopt module that is an alternative to the
 Arg module in the standard distribution. Getopt supports the general
 command line syntax of GNU getopt and getopt_long, but is close to the
 spirit of the Arg module: the programmer gives to the general parsing
 function a list of possible options, together with the behavior of
 these options.

Source package